In addition to speed increases, modern networks are more demanding
than earlier generations in that the
number of applications requiring network support has increased. Some of
these applications are user-based; some
are not. For example, it used to be that
only power users (and/or power holders) were issued laptop computers requiring wireless network access. Today,
a laptop is essentially a commodity
network device, issued to every worker
and ignored by the many who access
the network only from other mobile devices. Wireless access points may not
be everywhere in an enterprise network, but wireless access for users is
every where—and it has to be, because
users from all over the building require access from every corner of it.

Site surveys and wireless-signal verification are common practices that ensure wireless connectivity throughout
a workplace.

The extension of service providers’cellular wireless networks into the en-terprise has brought dramatic changeto the planning, design, installationand management of enterprise net-works. Once predominantly the domainof high-profile gathering spots like sta-diums and arenas, the on-premisesdistributed antenna system (DAS) isbecoming a practical necessity formany organizations whose users’ per-sonal mobile devices are business toolsrequiring ubiquitous connectivity.Wireless connectivity, then, is a us-er-based application that has evolvedand become more demanding overtime. It has gone from an applicationused by few to an application used bymany, requiring more and better in-frastructure in the process. Voice isanother, in that few enterprises em-ploy plain old telephone service (POTS)voice systems. Internet Protocol (IP)voice is now widespread.

In the span of time in which that
happened, other applications that are
not employed by each user became net-work-based. IP-based surveillance is a
widespread example. While IP surveillance may or may not be “owned” by a
company’s information technology department, it requires capable network
infrastructure, including cabling, to
operate successfully.

The network application du jour islighting. Currently, intelligent light-ing systems that employ Power overEthernet remote powering representan initial step into the realm of in-telligent buildings. Some of theseadvanced systems incorporate sensorsthat collect and share informationabout lighting use. Installers and usersof systems that have been employedto date report energy-efficiency gains.These connected lighting systems, andany other sensor-based building sys-tems that collect and share use data,are other examples of network appli-cations that must be planned for andsupported in enterprise environments.

Examining topologies

Designers, installers, and adminis-trators of cabling and wireless sys-tems used in today’s enterprise envi-ronments have far more toconsider, and far greater de-mands to meet, than wasthe case when horizontal da-ta-transmission speeds were100 Mbits/sec. As such, theperformance levels of cablingcomponents and systems, aswell as the physical structureof those systems, has evolvedaccordingly.In a white paper titled“Fiber backbone cabling inbuildings,” CommScope em-phasizes the importance ofdeploying high-performance,highly capable optical fiber. The com-pany explains, “Backbone cabling pro-vides interconnections between accessprovider space, entrance facilities,equipment rooms, telecommunicationrooms, and telecommunication enclo-sures. ANSI/TIA-568.3-D recommendsdeploying a hierarchical star topologyfor the backbone, with no more thantwo levels of crossconnections. Forthe simplest design, the main cross-connect in the equipment room feedsdirectly to the horizontal crosscon-nect in the telecommunication roomon each floor. Optional intermedi-ate crossconnects may be positionedIn its white paper “How Passive Optical LANs are enlightening the enterprise LAN,” theAssociation for Passive Optical LAN explains that a distributed antenna system may be ableto leverage the same fiber infrastructure as an optical LAN.